Biomedical subjects

T David Bourne

Publications and source records attributed to T David Bourne.

5 recordsLinked to original sources

PubMed2007

Fatal encephalitis in a patient with refractory celiac disease presenting with myorhythmia and carpal spasm.

We report the case of a woman with refractory celiac disease who developed abnormal spontaneous movements of the extremities and face consistent with myorhythmia. Investigation led to a diagnosis of encephalitis, confirmed by postmortem examination. The movements were likely caused by nonparaneoplastic encephalitis associated with refractory celiac disease. Etiologic and diagnostic considerations and treatment options are discussed.

Aged↗

PubMed2006

Reversible model of RNA toxicity and cardiac conduction defects in myotonic dystrophy.

Myotonic dystrophy (DM1), the most common muscular dystrophy in adults, is caused by an expanded (CTG)n tract in the 3' UTR of the gene encoding myotonic dystrophy protein kinase (DMPK), which results in nuclear entrapment of the 'toxic' mutant RNA and interacting RNA-binding proteins (such as MBNL1) in ribonuclear inclusions. It is unclear if therapy aimed at eliminating the toxin would be beneficial. To address this, we generated transgenic mice expressing the DMPK 3' UTR as part of an inducible RNA transcript encoding green fluorescent protein (GFP). We were surprised to find that mice overexpressing a normal DMPK 3' UTR mRNA reproduced cardinal features of myotonic dystrophy, including myotonia, cardiac conduction abnormalities, histopathology and RNA splicing defects in the absence of detectable nuclear inclusions. However, we observed increased levels of CUG-binding protein (CUG-BP1) in skeletal muscle, as seen in individuals with DM1. Notably, these effects were reversible in both mature skeletal and cardiac muscles by silencing transgene expression. These results represent the first in vivo proof of principle for a therapeutic strategy for treatment of myotonic dystrophy by ablating or silencing expression of the toxic RNA molecules.

3' Untranslated Regions↗

PubMed2006

Follicular lymphoma of the dura: case report.

OBJECTIVE: We present an unusual dural-based follicular lymphoma with radiological and macroscopic features similar to a meningioma. The unusual location of this tumor and its distinction from meningioma, mucosa-associated lymphoid tissue-type marginal zone B-cell lymphoma of the dura, and intraparenchymal central nervous system lymphoma, dramatically alters the patient's postoperative treatment. The case illustrates the clinical, radiological, and histological relevance of this rare entity. CLINICAL PRESENTATION: A 41-year-old Caucasian man with chronic bifrontal headaches and a raised area over his left frontal cranium that persisted for 1 year presented to the emergency room with nausea and vomiting. His family reported that the patient demonstrated increased irritability and aggressive behavior. A computed tomographic scan revealed a large mass of the left frontal convexity with edema and mass effect. Magnetic resonance imaging scans showed a 5-cm homogeneously enhancing mass in the left posterior frontal lobe. INTERVENTION: Preoperatively, the patient underwent angiography and embolization of the tumor. The patient underwent gross total resection of tumor. The dural-based tumor invaded the cranium and scalp. Neuropathological findings were consistent with low-grade follicular lymphoma. The patient is currently undergoing radiation and chemotherapy. CONCLUSION: The current case represents the first report of extensive intracranial dural involvement by a follicular lymphoma that shows a classic immunophenotype by immunohistochemistry and flow cytometry. The case illustrates the clinical and radiographic similarities between dural-based lymphoma and meningioma. Distinguishing dural-based follicular lymphoma from mucosa-associated lymphoid tissue-type lymphoma and from intraparenchymal primary central nervous system lymphomas, which are more often large cell lymphomas with more aggressive biological behavior, is essential for proper clinical management.

Dura Mater↗

PubMed2006

Primary disseminated leptomeningeal oligodendroglioma with 1p deletion. Case report.

The authors report the case of a 2-year-old boy with a primary, diffuse leptomeningeal oligodendroglioma in which the deletion of chromosome arm lp was identified by performing a fluorescence in situ hybridization (FISH) analysis. This previously healthy child initially presented with malaise, anorexia, nausea, vomiting, and macrocephaly. Imaging studies confirmed the presence of hydrocephalus, and a ventriculoperitoneal shunt was placed. The postoperative course was complicated by emesis, continued weight loss, and numerous seizurelike episodes. A contrast-enhanced magnetic resonance imaging study performed approximately 10 weeks postoperatively showed diffuse leptomeningeal thickening and enhancement without evidence of an intraparenchymal mass lesion. A right frontal lobe brain biopsy revealed a hypercellular proliferation of small oligodendroglioma-like cells, which occupied the leptomeninges diffusely and spared the underlying cortical gray matter. The tumor cells displayed prominent perinuclear clearing and had evenly spaced, uniformly round nuclei. Occasional mitotic figures were observed. Background vessels were thin and delicate, and there was no evidence of necrosis. The tumor cells showed strong immunoreactivity for S100 protein; the results of immunohistochemical staining were negative for glial fibrillary acidic protein, vimentin, epithelial membrane antigen, NeuN, and synaptophysin. The deletion of lp was demonstrated by FISH analysis; lq, 19p, and 19q were intact. This appears to be the first reported case of a primary diffuse leptomeningeal oligodendroglioma in which a lp deletion was identified.

Biopsy↗

PubMed2005

Evidence-based principles and practices in pathology: selected problem areas.

Contrary to the intuitive impression of most pathologists, there are still many areas in laboratory medicine where evidence-based medicine (EBM) principles are not applied. These include aspects of both anatomic and clinical pathology. Some non-EBM practices are perpetuated by clinical "consumers" of laboratory services, because of inadequate education, habit, or over-reliance on empirical factors. Other faulty procedures are pathologist-driven, with similar underpinnings. This overview considers several exemplary problem areas representing non-EBM practices in the hospital laboratory. Such examples include ideas and techniques centering on metastatic malignancies, "targeted" oncological therapy, analysis of surgical margins in the excision of neoplasms, general laboratory testing and data utilization, evaluation of selected coagulation defects, administration of blood products, and analysis of hepatic iron-overload syndromes. The concepts illustrating departures from EBM are discussed for each of those topics.

Blood Coagulation↗